| Abstract |
A comparison is made of battery charger topologies for electric vehicles. The chargers are all off-board, and capable of active power line conditioning and bi-directional power flow to compensate local utilities during peak power loads. The active power line conditioning capability is important, since an increase of battery chargers based on ordinary diode rectifiers would increase the low order harmonic content in grid currents. The battery chargers studied are one hard switched with a voltage-stiff de link, and three soft switched with quasi-resonant de links. Performance characteristics and energy conversion efficiency were evaluated from simulations. Indeed, the results imply that quasi resonant topologies have higher efficiency than hard switched. The drawback with the soft switched de links studied is the additional components, active and passive, needed for quasi-resonant operation. In battery charger applications, where high power efficiency is of prime interest, quasi-resonant topologies should be chosen. |
